1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21 /*
22 * Copyright 2017 Joyent Inc
23 * Copyright 2009 Sun Microsystems, Inc. All rights reserved.
24 * Use is subject to license terms.
25 */
26 /* Copyright (c) 1984, 1986, 1987, 1988, 1989 AT&T */
27 /* All Rights Reserved */
28
29 #include <stdio.h>
30 #include <stdlib.h>
31 #include <signal.h>
32 #include <syslog.h>
33 #include <string.h>
34 #include <stropts.h>
35 #include <errno.h>
36 #include <sys/netconfig.h>
37 #include <sys/mntent.h>
38 #include <sys/mnttab.h>
39 #include <sys/param.h>
40 #include <sys/time.h>
41 #include <sys/debug.h>
42 #ifdef notdef
43 #include <netconfig.h>
44 #endif
45 #include <sys/stat.h>
46 #include <sys/file.h>
47 #include <sys/fs/ufs_quota.h>
48 #include <netdir.h>
49 #include <rpc/rpc.h>
50 #include <rpcsvc/rquota.h>
51 #include <tiuser.h>
52 #include <unistd.h>
53 #include <dlfcn.h>
54 #include <libzfs.h>
55
56 #define QFNAME "quotas" /* name of quota file */
57 #define RPCSVC_CLOSEDOWN 120 /* 2 minutes */
58
59 struct fsquot {
60 char *fsq_fstype;
61 struct fsquot *fsq_next;
62 char *fsq_dir;
63 char *fsq_devname;
64 dev_t fsq_dev;
65 };
66
67 struct fsquot *fsqlist = NULL;
68
69 typedef struct authunix_parms *authp;
70
71 static int request_pending; /* Request in progress ? */
72
73 void closedown();
74 void dispatch();
75 struct fsquot *findfsq();
76 void freefs();
77 int getdiskquota();
78 void getquota();
79 int hasquota();
80 void log_cant_reply();
81 void setupfs();
82 static void zexit();
83
84 static libzfs_handle_t *(*_libzfs_init)(void);
85 static void (*_libzfs_fini)(libzfs_handle_t *);
86 static zfs_handle_t *(*_zfs_open)(libzfs_handle_t *, const char *, int);
87 static void (*_zfs_close)(zfs_handle_t *);
88 static int (*_zfs_prop_get_userquota_int)(zfs_handle_t *, const char *,
89 uint64_t *);
90 static libzfs_handle_t *g_zfs = NULL;
91
92 /*
93 * Dynamically check for libzfs, in case the user hasn't installed the SUNWzfs
94 * packages. 'rquotad' supports zfs as an option.
95 */
96 static void
load_libzfs(void)97 load_libzfs(void)
98 {
99 void *hdl;
100
101 if (g_zfs != NULL)
102 return;
103
104 if ((hdl = dlopen("libzfs.so", RTLD_LAZY)) != NULL) {
105 _libzfs_init = (libzfs_handle_t *(*)(void))dlsym(hdl,
106 "libzfs_init");
107 _libzfs_fini = (void (*)())dlsym(hdl, "libzfs_fini");
108 _zfs_open = (zfs_handle_t *(*)())dlsym(hdl, "zfs_open");
109 _zfs_close = (void (*)())dlsym(hdl, "zfs_close");
110 _zfs_prop_get_userquota_int = (int (*)())
111 dlsym(hdl, "zfs_prop_get_userquota_int");
112
113 if (_libzfs_init && _libzfs_fini && _zfs_open &&
114 _zfs_close && _zfs_prop_get_userquota_int)
115 g_zfs = _libzfs_init();
116 }
117 }
118
119 /*ARGSUSED*/
120 int
main(int argc,char * argv[])121 main(int argc, char *argv[])
122 {
123 register SVCXPRT *transp;
124
125 load_libzfs();
126
127 /*
128 * If stdin looks like a TLI endpoint, we assume
129 * that we were started by a port monitor. If
130 * t_getstate fails with TBADF, this is not a
131 * TLI endpoint.
132 */
133 if (t_getstate(0) != -1 || t_errno != TBADF) {
134 char *netid;
135 struct netconfig *nconf = NULL;
136
137 openlog("rquotad", LOG_PID, LOG_DAEMON);
138
139 if ((netid = getenv("NLSPROVIDER")) == NULL) {
140 struct t_info tinfo;
141
142 if (t_sync(0) == -1) {
143 syslog(LOG_ERR, "could not do t_sync");
144 zexit(1);
145 }
146 if (t_getinfo(0, &tinfo) == -1) {
147 syslog(LOG_ERR, "t_getinfo failed");
148 zexit(1);
149 }
150 if (tinfo.servtype == T_CLTS) {
151 if (tinfo.addr == INET_ADDRSTRLEN)
152 netid = "udp";
153 else
154 netid = "udp6";
155 } else {
156 syslog(LOG_ERR, "wrong transport");
157 zexit(1);
158 }
159 }
160 if ((nconf = getnetconfigent(netid)) == NULL) {
161 syslog(LOG_ERR, "cannot get transport info");
162 }
163
164 if ((transp = svc_tli_create(0, nconf, NULL, 0, 0)) == NULL) {
165 syslog(LOG_ERR, "cannot create server handle");
166 zexit(1);
167 }
168 if (nconf)
169 freenetconfigent(nconf);
170
171 if (!svc_reg(transp, RQUOTAPROG, RQUOTAVERS, dispatch, 0)) {
172 syslog(LOG_ERR,
173 "unable to register (RQUOTAPROG, RQUOTAVERS).");
174 zexit(1);
175 }
176
177 (void) sigset(SIGALRM, (void(*)(int)) closedown);
178 (void) alarm(RPCSVC_CLOSEDOWN);
179
180 svc_run();
181 zexit(1);
182 /* NOTREACHED */
183 }
184
185 /*
186 * Started from a shell - fork the daemon.
187 */
188
189 switch (fork()) {
190 case 0: /* child */
191 break;
192 case -1:
193 perror("rquotad: can't fork");
194 zexit(1);
195 default: /* parent */
196 zexit(0);
197 }
198
199 /*
200 * Close existing file descriptors, open "/dev/null" as
201 * standard input, output, and error, and detach from
202 * controlling terminal.
203 */
204 closefrom(0);
205 (void) open("/dev/null", O_RDONLY);
206 (void) open("/dev/null", O_WRONLY);
207 (void) dup(1);
208 (void) setsid();
209
210 openlog("rquotad", LOG_PID, LOG_DAEMON);
211
212 /*
213 * Create datagram service
214 */
215 if (svc_create(dispatch, RQUOTAPROG, RQUOTAVERS, "datagram_v") == 0) {
216 syslog(LOG_ERR, "couldn't register datagram_v service");
217 zexit(1);
218 }
219
220 /*
221 * Start serving
222 */
223 svc_run();
224 syslog(LOG_ERR, "Error: svc_run shouldn't have returned");
225 return (1);
226 }
227
228 void
dispatch(rqstp,transp)229 dispatch(rqstp, transp)
230 register struct svc_req *rqstp;
231 register SVCXPRT *transp;
232 {
233
234 request_pending = 1;
235
236 switch (rqstp->rq_proc) {
237 case NULLPROC:
238 errno = 0;
239 if (!svc_sendreply(transp, xdr_void, 0))
240 log_cant_reply(transp);
241 break;
242
243 case RQUOTAPROC_GETQUOTA:
244 case RQUOTAPROC_GETACTIVEQUOTA:
245 getquota(rqstp, transp);
246 break;
247
248 default:
249 svcerr_noproc(transp);
250 break;
251 }
252
253 request_pending = 0;
254 }
255
256 void
closedown()257 closedown()
258 {
259 if (!request_pending) {
260 int i, openfd;
261 struct t_info tinfo;
262
263 if (!t_getinfo(0, &tinfo) && (tinfo.servtype == T_CLTS))
264 zexit(0);
265
266 for (i = 0, openfd = 0; i < svc_max_pollfd && openfd < 2; i++) {
267 if (svc_pollfd[i].fd >= 0)
268 openfd++;
269 }
270
271 if (openfd <= 1)
272 zexit(0);
273 }
274 (void) alarm(RPCSVC_CLOSEDOWN);
275 }
276
277 static int
getzfsquota(uid_t user,char * dataset,struct dqblk * zq)278 getzfsquota(uid_t user, char *dataset, struct dqblk *zq)
279 {
280 zfs_handle_t *zhp = NULL;
281 char propname[ZFS_MAXPROPLEN];
282 uint64_t userquota, userused;
283
284 if (g_zfs == NULL)
285 return (1);
286
287 if ((zhp = _zfs_open(g_zfs, dataset, ZFS_TYPE_DATASET)) == NULL) {
288 syslog(LOG_ERR, "can not open zfs dataset %s", dataset);
289 return (1);
290 }
291
292 (void) snprintf(propname, sizeof (propname), "userquota@%u", user);
293 if (_zfs_prop_get_userquota_int(zhp, propname, &userquota) != 0) {
294 _zfs_close(zhp);
295 return (1);
296 }
297
298 (void) snprintf(propname, sizeof (propname), "userused@%u", user);
299 if (_zfs_prop_get_userquota_int(zhp, propname, &userused) != 0) {
300 _zfs_close(zhp);
301 return (1);
302 }
303
304 zq->dqb_bhardlimit = userquota / DEV_BSIZE;
305 zq->dqb_bsoftlimit = userquota / DEV_BSIZE;
306 zq->dqb_curblocks = userused / DEV_BSIZE;
307 _zfs_close(zhp);
308 return (0);
309 }
310
311 void
getquota(rqstp,transp)312 getquota(rqstp, transp)
313 register struct svc_req *rqstp;
314 register SVCXPRT *transp;
315 {
316 struct getquota_args gqa;
317 struct getquota_rslt gqr;
318 struct dqblk dqblk;
319 struct fsquot *fsqp;
320 struct timeval tv;
321 bool_t qactive;
322
323 gqa.gqa_pathp = NULL; /* let xdr allocate the storage */
324 if (!svc_getargs(transp, xdr_getquota_args, (caddr_t)&gqa)) {
325 svcerr_decode(transp);
326 return;
327 }
328 /*
329 * This authentication is really bogus with the current rpc
330 * authentication scheme. One day we will have something for real.
331 */
332 CTASSERT(sizeof (authp) <= RQCRED_SIZE);
333 if (rqstp->rq_cred.oa_flavor != AUTH_UNIX ||
334 (((authp) rqstp->rq_clntcred)->aup_uid != 0 &&
335 ((authp) rqstp->rq_clntcred)->aup_uid != (uid_t)gqa.gqa_uid)) {
336 gqr.status = Q_EPERM;
337 goto sendreply;
338 }
339 fsqp = findfsq(gqa.gqa_pathp);
340 if (fsqp == NULL) {
341 gqr.status = Q_NOQUOTA;
342 goto sendreply;
343 }
344
345 bzero(&dqblk, sizeof (dqblk));
346 if (strcmp(fsqp->fsq_fstype, MNTTYPE_ZFS) == 0) {
347 if (getzfsquota(gqa.gqa_uid, fsqp->fsq_devname, &dqblk)) {
348 gqr.status = Q_NOQUOTA;
349 goto sendreply;
350 }
351 qactive = TRUE;
352 } else {
353 if (quotactl(Q_GETQUOTA, fsqp->fsq_dir,
354 (uid_t)gqa.gqa_uid, &dqblk) != 0) {
355 qactive = FALSE;
356 if ((errno == ENOENT) ||
357 (rqstp->rq_proc != RQUOTAPROC_GETQUOTA)) {
358 gqr.status = Q_NOQUOTA;
359 goto sendreply;
360 }
361
362 /*
363 * If there is no quotas file, don't bother to sync it.
364 */
365 if (errno != ENOENT) {
366 if (quotactl(Q_ALLSYNC, fsqp->fsq_dir,
367 (uid_t)gqa.gqa_uid, &dqblk) < 0 &&
368 errno == EINVAL)
369 syslog(LOG_WARNING,
370 "Quotas are not compiled "
371 "into this kernel");
372 if (getdiskquota(fsqp, (uid_t)gqa.gqa_uid,
373 &dqblk) == 0) {
374 gqr.status = Q_NOQUOTA;
375 goto sendreply;
376 }
377 }
378 } else {
379 qactive = TRUE;
380 }
381 /*
382 * We send the remaining time instead of the absolute time
383 * because clock skew between machines should be much greater
384 * than rpc delay.
385 */
386 #define gqrslt getquota_rslt_u.gqr_rquota
387
388 gettimeofday(&tv, NULL);
389 gqr.gqrslt.rq_btimeleft = dqblk.dqb_btimelimit - tv.tv_sec;
390 gqr.gqrslt.rq_ftimeleft = dqblk.dqb_ftimelimit - tv.tv_sec;
391 }
392
393 gqr.status = Q_OK;
394 gqr.gqrslt.rq_active = qactive;
395 gqr.gqrslt.rq_bsize = DEV_BSIZE;
396 gqr.gqrslt.rq_bhardlimit = dqblk.dqb_bhardlimit;
397 gqr.gqrslt.rq_bsoftlimit = dqblk.dqb_bsoftlimit;
398 gqr.gqrslt.rq_curblocks = dqblk.dqb_curblocks;
399 gqr.gqrslt.rq_fhardlimit = dqblk.dqb_fhardlimit;
400 gqr.gqrslt.rq_fsoftlimit = dqblk.dqb_fsoftlimit;
401 gqr.gqrslt.rq_curfiles = dqblk.dqb_curfiles;
402 sendreply:
403 errno = 0;
404 if (!svc_sendreply(transp, xdr_getquota_rslt, (caddr_t)&gqr))
405 log_cant_reply(transp);
406 }
407
408 int
quotactl(cmd,mountp,uid,dqp)409 quotactl(cmd, mountp, uid, dqp)
410 int cmd;
411 char *mountp;
412 uid_t uid;
413 struct dqblk *dqp;
414 {
415 int fd;
416 int status;
417 struct quotctl quota;
418 char mountpoint[256];
419 FILE *fstab;
420 struct mnttab mntp;
421
422 if ((mountp == NULL) && (cmd == Q_ALLSYNC)) {
423 /*
424 * Find the mount point of any ufs file system. this is
425 * because the ioctl that implements the quotactl call has
426 * to go to a real file, and not to the block device.
427 */
428 if ((fstab = fopen(MNTTAB, "r")) == NULL) {
429 syslog(LOG_ERR, "can not open %s: %m ", MNTTAB);
430 return (-1);
431 }
432 fd = -1;
433 while ((status = getmntent(fstab, &mntp)) == NULL) {
434 if (strcmp(mntp.mnt_fstype, MNTTYPE_UFS) != 0 ||
435 !(hasmntopt(&mntp, MNTOPT_RQ) ||
436 hasmntopt(&mntp, MNTOPT_QUOTA)))
437 continue;
438 (void) strlcpy(mountpoint, mntp.mnt_mountp,
439 sizeof (mountpoint));
440 strcat(mountpoint, "/quotas");
441 if ((fd = open64(mountpoint, O_RDWR)) >= 0)
442 break;
443 }
444 fclose(fstab);
445 if (fd == -1) {
446 errno = ENOENT;
447 return (-1);
448 }
449 } else {
450 if (mountp == NULL || mountp[0] == '\0') {
451 errno = ENOENT;
452 return (-1);
453 }
454 (void) strlcpy(mountpoint, mountp, sizeof (mountpoint));
455 strcat(mountpoint, "/quotas");
456
457 if ((fd = open64(mountpoint, O_RDONLY)) < 0) {
458 errno = ENOENT;
459 syslog(LOG_ERR, "can not open %s: %m ", mountpoint);
460 return (-1);
461 }
462 }
463 quota.op = cmd;
464 quota.uid = uid;
465 quota.addr = (caddr_t)dqp;
466
467 status = ioctl(fd, Q_QUOTACTL, "a);
468
469 close(fd);
470 return (status);
471 }
472
473 /*
474 * Return the quota information for the given path. Returns NULL if none
475 * was found.
476 */
477
478 struct fsquot *
findfsq(char * dir)479 findfsq(char *dir)
480 {
481 struct stat sb;
482 struct fsquot *fsqp;
483 static time_t lastmtime = 0; /* mount table's previous mtime */
484
485 /*
486 * If we've never looked at the mount table, or it has changed
487 * since the last time, rebuild the list of quota'd file systems
488 * and remember the current mod time for the mount table.
489 */
490
491 if (stat(MNTTAB, &sb) < 0) {
492 syslog(LOG_ERR, "can't stat %s: %m", MNTTAB);
493 return (NULL);
494 }
495 if (lastmtime == 0 || sb.st_mtime != lastmtime) {
496 freefs();
497 setupfs();
498 lastmtime = sb.st_mtime;
499 }
500
501 /*
502 * Try to find the given path in the list of file systems with
503 * quotas.
504 */
505
506 if (fsqlist == NULL)
507 return (NULL);
508 if (stat(dir, &sb) < 0)
509 return (NULL);
510
511 for (fsqp = fsqlist; fsqp != NULL; fsqp = fsqp->fsq_next) {
512 if (sb.st_dev == fsqp->fsq_dev)
513 return (fsqp);
514 }
515
516 return (NULL);
517 }
518
519 static void
setup_zfs(struct mnttab * mp)520 setup_zfs(struct mnttab *mp)
521 {
522 struct fsquot *fsqp;
523 struct stat sb;
524
525 if (stat(mp->mnt_mountp, &sb) < 0)
526 return;
527
528 fsqp = malloc(sizeof (struct fsquot));
529 if (fsqp == NULL) {
530 syslog(LOG_ERR, "out of memory");
531 zexit(1);
532 }
533 fsqp->fsq_dir = strdup(mp->mnt_mountp);
534 fsqp->fsq_devname = strdup(mp->mnt_special);
535 if (fsqp->fsq_dir == NULL || fsqp->fsq_devname == NULL) {
536 syslog(LOG_ERR, "out of memory");
537 zexit(1);
538 }
539
540 fsqp->fsq_fstype = MNTTYPE_ZFS;
541 fsqp->fsq_dev = sb.st_dev;
542 fsqp->fsq_next = fsqlist;
543 fsqlist = fsqp;
544 }
545
546 void
setupfs()547 setupfs()
548 {
549 struct fsquot *fsqp;
550 FILE *mt;
551 struct mnttab m;
552 struct stat sb;
553 char qfilename[MAXPATHLEN];
554
555 mt = fopen(MNTTAB, "r");
556 if (mt == NULL) {
557 syslog(LOG_ERR, "can't read %s: %m", MNTTAB);
558 return;
559 }
560
561 while (getmntent(mt, &m) == 0) {
562 if (strcmp(m.mnt_fstype, MNTTYPE_ZFS) == 0) {
563 setup_zfs(&m);
564 continue;
565 }
566
567 if (strcmp(m.mnt_fstype, MNTTYPE_UFS) != 0)
568 continue;
569 if (!hasquota(m.mnt_mntopts)) {
570 snprintf(qfilename, sizeof (qfilename), "%s/%s",
571 m.mnt_mountp, QFNAME);
572 if (access(qfilename, F_OK) < 0)
573 continue;
574 }
575 if (stat(m.mnt_special, &sb) < 0 ||
576 (sb.st_mode & S_IFMT) != S_IFBLK)
577 continue;
578 fsqp = malloc(sizeof (struct fsquot));
579 if (fsqp == NULL) {
580 syslog(LOG_ERR, "out of memory");
581 zexit(1);
582 }
583 fsqp->fsq_dir = strdup(m.mnt_mountp);
584 fsqp->fsq_devname = strdup(m.mnt_special);
585 if (fsqp->fsq_dir == NULL || fsqp->fsq_devname == NULL) {
586 syslog(LOG_ERR, "out of memory");
587 zexit(1);
588 }
589 fsqp->fsq_fstype = MNTTYPE_UFS;
590 fsqp->fsq_dev = sb.st_rdev;
591 fsqp->fsq_next = fsqlist;
592 fsqlist = fsqp;
593 }
594 (void) fclose(mt);
595 }
596
597 /*
598 * Free the memory used by the current list of quota'd file systems. Nulls
599 * out the list.
600 */
601
602 void
freefs()603 freefs()
604 {
605 register struct fsquot *fsqp;
606
607 while ((fsqp = fsqlist) != NULL) {
608 fsqlist = fsqp->fsq_next;
609 free(fsqp->fsq_dir);
610 free(fsqp->fsq_devname);
611 free(fsqp);
612 }
613 }
614
615 int
getdiskquota(fsqp,uid,dqp)616 getdiskquota(fsqp, uid, dqp)
617 struct fsquot *fsqp;
618 uid_t uid;
619 struct dqblk *dqp;
620 {
621 int fd;
622 char qfilename[MAXPATHLEN];
623
624 snprintf(qfilename, sizeof (qfilename), "%s/%s", fsqp->fsq_dir, QFNAME);
625 if ((fd = open64(qfilename, O_RDONLY)) < 0)
626 return (0);
627 (void) llseek(fd, (offset_t)dqoff(uid), L_SET);
628 if (read(fd, dqp, sizeof (struct dqblk)) != sizeof (struct dqblk)) {
629 close(fd);
630 return (0);
631 }
632 close(fd);
633 if (dqp->dqb_bhardlimit == 0 && dqp->dqb_bsoftlimit == 0 &&
634 dqp->dqb_fhardlimit == 0 && dqp->dqb_fsoftlimit == 0) {
635 return (0);
636 }
637 return (1);
638 }
639
640 /*
641 * Get the client's hostname from the transport handle
642 * If the name is not available then return "(anon)".
643 */
644 struct nd_hostservlist *
getclientsnames(transp)645 getclientsnames(transp)
646 SVCXPRT *transp;
647 {
648 struct netbuf *nbuf;
649 struct netconfig *nconf;
650 static struct nd_hostservlist *serv;
651 static struct nd_hostservlist anon_hsl;
652 static struct nd_hostserv anon_hs;
653 static char anon_hname[] = "(anon)";
654 static char anon_sname[] = "";
655
656 /* Set up anonymous client */
657 anon_hs.h_host = anon_hname;
658 anon_hs.h_serv = anon_sname;
659 anon_hsl.h_cnt = 1;
660 anon_hsl.h_hostservs = &anon_hs;
661
662 if (serv) {
663 netdir_free((char *)serv, ND_HOSTSERVLIST);
664 serv = NULL;
665 }
666 nconf = getnetconfigent(transp->xp_netid);
667 if (nconf == NULL) {
668 syslog(LOG_ERR, "%s: getnetconfigent failed",
669 transp->xp_netid);
670 return (&anon_hsl);
671 }
672
673 nbuf = svc_getrpccaller(transp);
674 if (nbuf == NULL) {
675 freenetconfigent(nconf);
676 return (&anon_hsl);
677 }
678 if (netdir_getbyaddr(nconf, &serv, nbuf)) {
679 freenetconfigent(nconf);
680 return (&anon_hsl);
681 }
682 freenetconfigent(nconf);
683 return (serv);
684 }
685
686 void
log_cant_reply(transp)687 log_cant_reply(transp)
688 SVCXPRT *transp;
689 {
690 int saverrno;
691 struct nd_hostservlist *clnames;
692 register char *name;
693
694 saverrno = errno; /* save error code */
695 clnames = getclientsnames(transp);
696 if (clnames == NULL)
697 return;
698 name = clnames->h_hostservs->h_host;
699
700 errno = saverrno;
701 if (errno == 0)
702 syslog(LOG_ERR, "couldn't send reply to %s", name);
703 else
704 syslog(LOG_ERR, "couldn't send reply to %s: %m", name);
705 }
706
707 char *mntopts[] = { MNTOPT_QUOTA, NULL };
708 #define QUOTA 0
709
710 /*
711 * Return 1 if "quota" appears in the options string
712 */
713 int
hasquota(opts)714 hasquota(opts)
715 char *opts;
716 {
717 char *value;
718
719 if (opts == NULL)
720 return (0);
721 while (*opts != '\0') {
722 if (getsubopt(&opts, mntopts, &value) == QUOTA)
723 return (1);
724 }
725
726 return (0);
727 }
728
729 static void
zexit(int n)730 zexit(int n)
731 {
732 if (g_zfs != NULL)
733 _libzfs_fini(g_zfs);
734 exit(n);
735 }
736